Greg Yang@TheGregYang
I've been suffering from Lyme disease.
I'm stepping back from xAI into an informal advisory role so I can go founder mode on my health, starting today.
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The symptoms started when I got sick (cold, flu, or COVID -- I'm not sure which) in early 2025. I distinctly felt less energetic, less creative, and less agentic even weeks after "recovery." After that, my condition ebbed and flowed, but the lows kept getting lower.
Accidentally eating the wrong thing would make me extremely tired, taking days to recover. Working out would leave my whole body feeble for days. There was a week where I slept 12 hours a day and still couldn't recover.
Lyme is famously hard to diagnose, but luckily I have an incredible doctor. He suspected these symptoms, far from being just in my head, indicated immune issues. Detective work over a few rounds of testing revealed I have Lyme disease.
I was very surprised because Lyme is said to come from tick bites (where the bump looks like a target), but I don't ever remember having one. Likely I contracted Lyme a long time ago, but until I pushed myself hard building xAI and weakened my immune system, the symptoms weren't noticeable.
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Overall, I actually feel lucky to have discovered this early. Lyme is a serious disease that only gets harder to treat with age -- patients discovering it in their 50s or 60s have a much tougher time. Lyme can also be debilitating, leaving its victims bedridden, but luckily I'm still functional and can take care of myself day to day.
So while some folks have said "you shouldn't have pushed yourself so hard," I'm glad I did. I found this issue early, and now I can fix it so I can push myself even harder when I rebound.
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Chronic Lyme is not well understood in the literature or by the public. For folks suffering from it, it can be a lonely fight. But I hope my story can make it just a little less lonely.